Stub out initial NavigationController browser implementation

content/browser/nav_controller/nav_controller_dispatcher_host.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_NAV_CONTROLLER_NAV_CONTROLLER_DISPATCHER_HOST_H_
+#define CONTENT_BROWSER_NAV_CONTROLLER_NAV_CONTROLLER_DISPATCHER_HOST_H_
+
+#include "content/public/browser/browser_message_filter.h"
+
+class GURL;
+
+namespace content {
+
+class NavControllerContext;
+
+class NavControllerDispatcherHost : public BrowserMessageFilter {
+ public:
+  explicit NavControllerDispatcherHost(NavControllerContext* context);
+
+  // BrowserIOMessageFilter implementation
+  virtual bool OnMessageReceived(const IPC::Message& message,
+                                 bool* message_was_ok) OVERRIDE;
+
+ protected:
+  virtual ~NavControllerDispatcherHost();
+
+ private:
+  // IPC Message handlers
+  void OnRegisterController(int32 host_id,
+                            const string16& scope,
+                            const GURL& script_url);
+  void OnUnregisterController(int32 host_id, const string16& scope);
+
+  scoped_refptr<NavControllerContext> context_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_NAV_CONTROLLER_NAV_CONTROLLER_DISPATCHER_HOST_H_